This invention is related to a means for attaching an injection nozzle to a cylinder head for an injection-internal combustion engine and is more particularly concerned with a nozzle which is insertable into a nozzle receiving bore which nozzle is forced axially against a section of the receiving bore by a clamp means on the cylinder head. The clamp means is comprised of a threaded guide hole, and a collar having a member, preferably a forked-shaped pressure piece, detachably connecting the nozzle and the clamp means.
The prior art, particularly French Pat. No. 1,538,194, discloses a screw on a spiral spring at a distance from the channel in the cylinder head for receiving the injection nozzle. The free end of the spring engages an annular extension on the nozzle body in the shape of a fork and biases the extension sealingly against the edge of the channel to secure the injection nozzle in its operating position. The spring is incapable of absorbing the axial pressure generated in diesel engines. Additionally, a considerable bending strain on the attaching screw will occur at the transition point between the screw head and the shaft of the screw due to the strain on the projecting spring.
Another prior art method for attachment of a nozzle on injection-internal combustion engines uses a so-called fork bride which is supported on one end by placement of its fork-like pressure piece against milled slots on both sides of the nozzle holder and on the other end against a plane milling slot of the cylinder head and which are secured by a single clamping screw passing through an eye in the middle part of the fork bride. This construction requires an additional processing expenditure for the plane supporting surface on the cylinder head. The machining of the plane frequently causes difficulty due to the very restricted spatial conditions on the top side of the cylinder head. Additionally, the fork bride may become loose during the release as well as during tightening of the injection line on the nozzle due to the high torque generated. Further, due to the relatively great play of the clamping screw in the eye of the fork bride, precisely maintaining the insertion position of the nozzle holder in the direction sought, is compromised. Consequently, errors in operating direction will result for the injection holes of the nozzle which is particularly disadvantageous in the case of an insertion position of the nozzle which is oblique in relation to the combustion cylinder axis.